Circuit breaker



April 3, 1928.

F. W. ROLLER CIRCUIT BREAKER Filed Sept. 24. 1924 2 Sheets-Shoot 1 INVENTOR Makm 'ITORNEYS April 3, 1928.

1,665,113 F. W. ROLLER CIRCUIT BREAKER Filed Sept. 24, 1924 2 Sheets-$110M 2 ATTORNEYS Patented Apr. 3, 1928.

UNITED STATES 1,665,113 PATENT OFFICE.

FRANK w. ROLLER, OF EAST ORANGE, NEW JERSEY, ASSIGKOB '10 nomn-m'rn run, A CORPORATION NEW You.

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Application filed September a4, 1924. Serial no. 13am.

This application relates toautomatio cir-, cuit breakers and although shown and described herein in the form of a multi-pole circuit breaker, the invention is equally well adapted as to some features to single-pole breakers. In the particular embodiment de- M'l'lbfid, the invention is shown as applied to a three-pole breaker adapted for the control of the lines of a three-wire circuit.

The general object of this invention is to provide a. circuit breaker which will be of a simple form of construction anddurable and dependable in operation and embody the various features with the attendant advan-- tages hereinafter referred'to. I

One particular object of the invention is to prevent the operator from holding the breaker closed, while an abnormal condition of the circuit exists, or in other words to always permit the opening of the breaker when an overload exists, or other abnormal circuit conditions which may be desirable to safeguard against. A further object of the invention is to insure the immediate openlog of the circuit breaker automatically upon the occurrence of a predetermined overload current, and,also insure the automatic opening of the breaker upon the occur-' rence of overload currents less than said predetermined value after the same has continued for a certain length of time, depending upon the magnitude of the current. A further object is to insure the opening of all poles of the breaker when an abnormal condition exists in any one of the circuits. Another object is to insure a quick closing of the circuit breaker contacts with suflicient pressure exerted between the contacts to insure good electrical contact of the switch parts and to also insure the quick oglening of the circuit breaker contacts, w ether opened manually or automatically. Another object is to provide a simple form of operating and controlling mechanism which will avoid the necessity of using the commonly used toggle mechanism and reduce the number of parts to a minimum. I thereby secure a simple and compact form of construction. Other objects and advantages of myinvention will be understood fronr'the following description and accom anyingdrawings which illustrate a pre erred embodiment thereof.

Fig. 1 is a plan view of my improved breaker with the enclosing cover removed;

Fig 2 is a side view of the same, partly in section, showing the breaker in o n tlon; Fig. 3 is a view similar to Fig. 2 with the parts in engaging position for closi and Fig. 4 is a 'simllar view showing the .9 circuit reaker in closed position.

The circuit breaker parts are all mounted upon a base 1 of insulating material, which base and parts. carried thereby, are remov-" able from .a box or casing 2 below the base .1, which casing is ada ted to contain 011. The breaker is enclose at the to by a removable cover not shown' in the di awmg.

' The three-wire incoming leads are shown 79 at the left of the drawings connected to terminal posts 3 which are mounted upon the base 1 and carry at their lower ends the fixed contacts 4. The three yieldable movable contacts are shown at 5 and are respectively carried by three conducting. bars 6 which in turn are pivotally mounted in the lower ends of depending brackets 7 secured to the under face of the base 1. The three bars 6 are mechanically connected together 89 by a cross block 8 of insulating material. Secured to one of the bars 6, and preferablfy the middle bar, is a U-shaped element 9.

- This element is insulated from its bar 6 and pivotally carries between its upper ends a pair of upwardly extending links 10. Between the upper ends of the links 10 is located a pin or roller 11. From the outer ends of the pin 11 and from the outside of the links 10 extend a pair of links 12' which 00- are in turn pivotally connected to two of the downwardly extending arms of brackets 7. The breaker is biased to open position by the spring effect of the brushes 5, by gravity and also by action of the spring 13 05 secured at its upper end to the base 1 and at its lower end to an extension 14 from one of the pivoted bars 6. It is evident that when an upward pull is exerted upon the pin 11 the breaker will be closed and held closed, but when the pin 11 is released, the breaker will be thrown to its biased normally open position. I

' The outgoing leads are shown at the right hand side of the drawings and are connected 10a to three binding posts 15 which are mounted on the base 1 and extend to the under side thereof. From the lower end of each of the outer binding posts 15 extends a bi-metallic thermostatic strip 16, which carries at its no inner end a terminal 17 and a plate 18, which lunger 19' which explate extends under a e' base 1 and which tends freely through t will afterwards he explained. Each of the two plates 18 has its respective lunger 19, one for each of two of the three ines of the circuit. From'the two terminals 17 flexible leads 20 extendto and are electrically -con-.

' nected to the lower end of conducting posts 21 which extend u wardly through the base. The upper ends 0 two posts21 are electri cally connected respectively to a pair of overload coils 22,the other ends of the coils being 7 lower end of the middle bin ing post 15 is of thebase and is adapted to engage the ex-- electrically connected directly to the middle conducting bar 6 of the breaker through a flexible lead 25. A back stop 26 of insulating material extendsdown from the under side tension 14 to limit the open position of the movable contacts.

The operatin arm 27 of the breaker is connected to a shaft 27 which has a bearing in an outer support 27 and has an inner U-shape-d portion 27 the inner end of which is .pivotally mounted between a pair of supports 27 fixed to the base; From the inner end of the part 27 extends an arm 27 to the right,the end of which arm is adapted to engage the base 1 and serve as a stop for the handle element when thrown to the right. From the inner end of part 27 another arm -27 extends to the left which is adapted to engage the base and serve as a stop for the handle element when thrown to the left.

Thearm 27 also carries two opposite outwardly extending. parts 27 at the end of which are connected respectively the operating springs 28. The right hand ends of these springs are connected to the outer ends respectively of pins 29 which in turn are fixed to and carried by a pair of links 30. These links are pivotally mounted at their left hand ends between supports 27"; and the links are connected together at their right hand ends by a pin 30. When the links 30 are caused to move downwardly about their pivotal support, the right hand end of the links will strike against the base which serves as a stop for limiting their movement in one direction. Movement in theopposite direction is limited by the pins 29' engaging a pair of plates 31 fixed to the base and which have their left hand portions-under-cut to serve as a sto .for the pins 29. Pivotally mounted on the inks30 is a controlling element comprising a cross-bar 32 at its upper end, from which downward-1y extend at the middle portion a pair of arms 32. These-arms embrace the links 30, being pivotally connected thereto, and extend downwardly throu h the base and unite .to' form a downward y extending latch 32*. This latch-is adapted to engagethe pin 11 and is biased towards the pin 11 by a spring 33 connected between the latcharm 32 and a support fixed tothe under side of the base.

The automatic tripping of this latch and release of the movable switch contacts from the operating mechanism of the breaker is controlled by the overload coils 22. Each overload coil is mounted upon the middle leg 34 of, anyE-shaped magnet, the three arms of the magnet extending upwardly. On the left hand arm of each magnet is pivotally mounted an armature 35. Secured to the back ofeach armature is a stri 35 which has a depending tongue 35*. hen either of the armatures 35 is attracted by its respective magnet, the tongue 35 will engage the bar 32 forcing it to the left and causing the latch 32 to be thrown to the right. A triangularly shaped plate 35 is ad ustably secured by screws to the inner end ofeach armature and is adapted to engage the pivotal support of the armature to serve as a stop to limit the outer position of the armature 35. Secured to the inner end of each armature '35 is a spring 35 which extends downwardly and is secured at its inner end to the frame of the overload magnet. This spring may be adjustable to the desired tension for normally holding the armature 35 in its outer position. Secured to the inner end of each armature is also a pin 35 from which depends a rod 36. This rod is threaded atits lower end and carries the previously mentioned plunger 19 which is adjustable in position on the threaded rod 36.

In operation, let us first assume that the breaker is open and the parts in engaging position ready for closing as shown in Fi 3. In this position the operating handle is at the left which has thrown the outer ends of springs 28 downwardly as shown. When the handle is moved to the right the. left hand ends of the operating s rings 28 are moved upwardly until, when t e line of action passes the pivot of the links 30, the springs cause the inner ends of the links 30 to be thrown upwardly to the position shown in Fig. 4. This upward movement of the links carries the latch arm 32? therewith and, as this latch is in engagement with pin 11, the movable contactsof the breaker are thrown to closed position as shown in Fig. 4. Han overload exists suflicientto cause either one or both of the armatures 35 to be N curved sha 1,eea,1 is

attracted, the bar 32 will be pushed to the thrown downwardly across the pivotal sup port of the links 30 which thereby carries the latch 32" downwardly to engage the pin 11, the parts then assuming the position shown in Fig.3. The breaker may now be closed by throwing the 0 erating handle to the right, as previously escribed, the parts then assuming the 'posltlon shown in Flg. 4.

Considering now the delayed action overload responsive controlling means, we may assume the breaker to be in closed position shown in Fig. 4. Upon the occurrence of a sufliciently lar'ge overload, either one or both of the armatures 35 will be instantly attracted and cause the breaker to be immediately opened automatically. If, however, an overload exists which is not suflicient to instantly attract either one of the armatures 35, the passage of this overload current through either one or both of the thermostatic strips 16 will cause one or both of them to be subjected to an increasing temperature. This of course causes the strip 16 to assume a and cause its inner free end to be gradual y raised and cause the plate 18 to engage and gradually raise the plunger 19. If this assumed overload persists long enough, the raising of plunger 19 will con tinue and at the same time cause its armature 35 to gradually approach the poles of the overload magnet. When the armature 35 is finally brought to a position near enough to the poles ofthe magnet to be attracted by the magnet at the value which the overload current then has, it will then cause the breaker to be tripped and o ened automatically. Thus, if the overloa current is of moderate amount and persists long enough, the circuit breaker will be opened automatically after a predetermined time interval, the time interval depending upon the strength of the overload current passing; and the smaller the overload current the longer will be the time interval. This is due to two causes, first, a small overload current will take a longer time to distort the thermostatic strip and to bring the armature 35 to a position to be attracted by its magnet, and second, the smaller the overload current, the nearer must the armature 35 be brought to the poles of the magnet, before it will be'attracted. On the other hand if the overload current is very high, such as may be due to a short circuit condition, the breaker will be instantly opened as already explained. The above described automatic spring will, of course, occur when either or both of the armatures is attracted and thus protect all three lines from overload currents.

As a convenient means for showing whether the breaker is closed or opened, in v:ew of the breaker being enclosed and the position of the handle not being an indication of the position of the circuit breaker contacts, I have provided an indicator 37 which is pivotally supported on the base by an upwardly extending arm'37. The indicator is suitabl marked such as by the words Off an On and one or the other of these markings will appear through an opening in the casing according to the posit on of the circuitbreaker contacts. The indicator 37 has an arm 37 to the end of which is pivotally connected a bar 38 which extends downwardly throu h the base and is pivotally connected to t e outer end of the extension 14. In Fig. 2 the marking Otl' appears through the 'o ning in the cas ng andi t is evident that w en the breaker is moved to closed position as shown in Fig. 4 the indicator is thrown to a position so that the marking On appears opposite the opening in the casin Although I have descrlbed this breaker as being controlled by overload, it is evident that the control of the breaker may be made subject to other abnormal controlling cond tions by means Well understood by those skilled in the art. And although I have shown one particular embodiment of my invention, the same is subject to various modifications without departing from the scope of this invention.

I claim:

1. A circuit breaker comprising a )ivoted manually operated element, a secon pivoted element, a spring connected between said elements, a movable contact biased to open circuit position, releasable connecting means pivoted to-said second element and in releasing contact with said movable contact, and automatic tripping means for releasing said movable contact from said second element upon the'occurrence of an abnormal circuit condition.

2. A circuit breaker comprising a pivoted manually operated element, a second pivoted element, a spring connected between said elements, amovable contact, a latch device pivoted to said second element and connectmg said second element with said movable contact, and means for automatically releasing said latch device upon the occurrence of an abnormal circuit condition.

3. A circuit breaker comprising a base plate, a manually operated element pivotally mounted thereon, a second element pivotally mounted thereon, a spring connecting [III ' said elements, a movable contact-element on mal circuit condition.

4. A circuit breaker comprising a base plate, a manually operated element pivot:

' ally mounted on said base plate, a second element pivotally mounted on said base.

- plate, a spring connecting said elements and adapted by movement of, said manually operated element in oppositedirections to carry the'line of action of said spring across the pivot of said second named element, a movs able contact element on the-opposite side of said base plate, a latch adapted to releasably engage said contact element, said latch be ing pivotally connected with said second named element and extending through said base plate, and means for automatically releasing "said latch from said contact element upon the occurrence of an abnormal circuit condition. y e

5. A circuit breaker comprising a base plate, a manually movable element pivotally mounted thereon, 2i second element piv otally mounted thereon, a spring connecting said elements, a plurality of movable con-.

base plate, a latchextending throughilsaid base plate and releasably connected between said second element and said 'contactele ments, a plurality oteontrolling coils connected in the circuits of said breaker, said coils fhaving armatures respectively controlled thereby, and each of said armatures being adapted to engagesaid latch upon the, occurrence of an abnormal circuit condition in its respective controlling coil and thereby release said latch from said contact elements.

6. A circuit breaker comprising a base plate, a manually operated element pivotally mounted thereon, a second element'pivotally mounted thereon a spring connecting said elements and adapted by movement of said manual element to have th'e lineot ac support of said second,element,ia plurality of contact elements on the opposite side of said plate, a single latch releasably connecting said contact elementsEjiiiithsaidsecond element, a lurality oi-ov'erloadgmagnets on the side 0 said base'plate dpposite from.-

said contact elements and connected respec and the artively in certain of the circuits,

adapted matures .of said magnets each being tact elements on theopposite side of. saidinterval.

' extendin ment pivotally mounted thereon, a spring connecting said elements and having its line I of action adapted to be carried across the pivot of said second element u on movement of said 'nianually operated e ement for closing saidbreaker andretaining the same in closed osition under normal operating conditions, a controlling magnet having an armature for automatically opening said breaker upon the occurrence of an abnormal circuit condition and thermostatic means for varyi'ng the'controlling effect of said magnet upon the occurrence of an abnormal circuit condition when continued for a certain time interval.

8. A circuit breaker comprising. operating mechanism on one side of said plate for controlling the' closing of the breaker, a movable contact element of the breaker mounted on the opposite side of said plate, means comprisinga magnet and movable armature for automatically opening said breaker upon the occurrence of an abnormal circuit condition, said means being mounted on the opposite side of said plate from said contact element, and a thermostatic device mopnted 'on the same side of said plate as said. contact element. for varying the position of said armature in relation .to the poles of its magnet when an abnormal circuit condition 1s continued a certain time A circuit breaker comprising a base plate, \a -manually operated elementpivotaly mounted thereon, a second element pivotally mounted thereon, a sprin connecting said elements and having its line of action adapted to be carried across the, pivot of said second element upon movement of said manually operated element, a movable contact on the opposite side of'said plate, releasable means connected between said second element and said contact element and through said plate, an overload magnet tomatically releasing said releasable means upon the occurrence of a predetermined avinga movable armature for an overload current, a thermostatic device on the same side of said plate as said contact tion of the spring carried across the pivotal element, and means controlled by said therto engage said latch and release the same action. adapted to be carried across the pivot from said second element upon the occurrence of overload current in its respective overload magnet. 5

7. A circuit breaker comprising a pivoted manually operated element, a second eleof said second element u on movement of said manually operated e ement, a movable contact on the opposite side of'said plate, releasable means connected between said sec- 0ndv element and said contact elemenn and extending through said plate, an overload magnet havin a movable armature for automatically re easing said releasable means upon the occurrence of a predetermined overload current, a thermostatic device on the same side of said plate as said contact element, and a plunger connected to said armature and passing through said plate controlled by said thermostatic element.

11. A circuit breaker comprising a manually operated element, a second element piv-" otally mounted thereto, a spring connecting said elements and having its line of-ac tion adapted to be carried across the pivotof said second element upon movement of said manually operated element for closing the circuit breaker contacts during which operation energy is stored during the first part of the movement of said manually operated element and later expended to ac-- celerate the rapidity of the "closing movement of the circuit breaker contacts and. automatic means, acting independentlypf said first named means for quickly opening the breaker upon the occurrence of an abnormal circult condition.

12. A circuit breakercomprislng amanu- .ally operated element, a second element pivotally mounted thereto, a spring connecting said elements and having its line of action adapted to be carried across the pivot of said second element upon movement of said manually operated element for 0 ening the circuit breaker contacts durin w ich operation energy is stored during t e first part of the movement of said manually operated element and later expended to permit thefrapid opening movement of the circuit breaker contacts, and automatic means for controlling'the opening of the circuit breaker upon the occurrence of an abnormal circuit condition.

v 113., A circuit breaker comprising a manually operated element, a second element pivotally mounted thereto, a spring connecting said elements and having its line of action adapted to be carried across the pivot of said second element, upon movement of said manually operated element, for closing and opening the circuit breaker contacts during which movements energy is stored during the first part of the movement of said manuallyroperated element and later expended, whereby the rapidity of the movement of the contacts during the closing and opening movements of the circuit breaker contacts respectively is accelerated, and automatic FRANK W. ROLLER. 

